Fluorescein angiography of the eye

Fluorescein angiography is an imaging test that allows for detailed visualization of blood flow within the small blood vessels of the retina and the underlying choroid. The procedure involves injecting a special fluorescent dye, fluorescein, into a vein in the arm. Within approximately 20 seconds, the dye reaches the eyes, coloring the blood vessels. A specialized camera then captures a series of images, using blue light and specific filters to highlight the dye's passage and the vascular structures.

The primary purpose of this test is to diagnose a wide range of conditions affecting the retinal blood vessels. It can identify leaks from blood vessels, areas of blocked blood supply (ischemia), fluid accumulation (edema), and the growth of new, abnormal blood vessels. This test is crucial for diagnosing and monitoring eye conditions such as diabetic retinopathy, age related macular degeneration (AMD), retinal vein or artery occlusions, and various inflammatory conditions.

Before the test, you may be advised to avoid eating for a short period to minimize the risk of nausea. It is important to inform the medical staff about any history of allergies, especially to medications or contrast dyes, as well as any history of asthma. Please inform the medical team about any history of kidney disease. Breastfeeding mothers should discuss with the medical team regarding breastfeeding after the test, as the contrast dye is excreted in breast milk.

The test begins with the instillation of eye drops to dilate the pupils, a process that typically takes about 30 minutes. Following dilation, the fluorescein dye is injected into a vein in your arm. Within approximately 20 seconds, the dye circulates to your eyes. At this point, a specialized camera rapidly captures a series of images of the fundus (back of the eye), utilizing blue light and specific filters to enhance the visibility of the dye within the blood vessels. The imaging portion of the test usually lasts about 30 minutes.

Most side effects associated with fluorescein angiography are mild and temporary. Common reactions include mild nausea, vomiting, slight dizziness, and a rash or redness of the skin accompanied by itching. Additionally, if the dye leaks outside the vein at the injection site (extravasation), it can cause a localized burning sensation; you should alert the staff immediately if you feel pain at the IV site. More severe side effects, such as severe shortness of breath or a serious allergic reaction (anaphylaxis), are very rare. It is important to inform the medical team immediately if you experience any unusual symptoms during or after the test.

Following the test, you may notice a temporary yellowish tint to your skin and your urine may appear bright orange yellow; these effects typically resolve within 24 hours. Drinking water as usual is recommended to help flush the dye from your system. Due to pupil dilation, your vision will be blurred and light sensitive for several hours, so it is advisable to avoid driving and to have someone accompany you, bringing sunglasses. Seek medical advice if a rash or significant itching develops after the test. Breathing difficulty, throat or facial swelling, or fainting requires immediate emergency help.